The basic mechanical design of a dishwasher, especially a household dishwasher, is referred to as a platform. The platform of a dishwasher essentially comprises the washing compartment and the way in which the washing compartment is supported on the floor, e.g. by a mounting floor made of metal or plastic. Under some circumstances the platform, in addition to the aforementioned components, is also taken to mean the installation of or the option of installing functional components, e.g. pumps, heating, electrical or hydraulic plug-in connections, filter or water softening device and/or the housing.
The following platform is known from the prior art: A washing compartment is placed on a mounting floor made of plastic. The washing compartment with two sidewalls, a rear wall, a lower wall and an upper wall (only open to the front) is made entirely of stainless steel and is generally produced by means of bending and joining processes, e.g. welding, in general from a number of stainless steel plates. The mounting floor is therefore a tray open at the top, which for example is presented in applicant's EP 0 243 632 A2 and EP 0 243 631 B1.
Attached to the washing compartment made of stainless steel and/or to frame parts preferably made of metal, the housing (preferably embodied as coated metal plates) are normally attached to the dishwasher essentially at specific points or with small contact surfaces, for example by screw or clip connections. The housing thus consists of at least one separate outer wall. The washing compartment made of stainless steel is thus a separate component independent of the housing and not integrated into a housing typically made of plastic, i.e. especially connected to each other over a large surface area. The visible stainless steel surface in the washing compartment is thus not merely a coating or cladding of the housing, made of plastic for example, with stainless steel or a stainless steel plate overmolded during the injection molding of the plastic housing as in the EP 0 556 787 B2. To this extent housing and washing compartment are independent of each other. This constructive layout between housing and washing compartment also applies to the applicant's DE 101 56 423 A1 and EP 0 452 287 B1 as the prior art mentioned further below.
Known from EP 0 556 787 B2 is a platform with an upper part, containing two side walls a lower wall and an upper wall, in which the housing and the part of the washing compartment formed by the upper section form a unit and are double walled, i.e. made in one piece from plastic and are placed on a mounting floor as a base, likewise made of plastic. This invention therefore involves a platform concept other than that described above, which especially because of the use of plastic and the integrated connection between housing and washing compartment as a twin-wall plastic part in the upper section, differs from the above-mentioned prior art. For optical refinement at least a part of the visible surface of the floor of the washing chamber, which is embodied in one piece with the base made of plastic, can have a metallic surface.
In a development of the first platform described above (not EP 0 556 787 B2) a washing compartment is known from EP 0 452 287 B1 which merely features two side walls, a rear wall and an upper wall made of stainless steel (tub) and the lower wall of the washing compartment is formed by the mounting floor made of plastic, i.e. the mounting floor is thus not a tray open at the top as in EP 0 243 632 A2 and EP 0 243 631 B1, but a box essentially enclosed on all sides.
A platform with a stainless steel washing compartment made from two sidewalls, a rear wall and an upper wall is likewise known from the applicant's DE 101 56 423 A1. The lower wall of the washing compartment, is likewise formed from the mounting floor made of plastic.
This platform concept, especially known from the applicant's EP 0 452-287 B1 and DE 101 56 423 A1, in which the plastic mounting floor forms the lower wall of the washing compartment and feature a special housing, are more cost effective and simple to produce. The disadvantage of these two last-mentioned platforms is however, that in the inside of the washing compartment, i.e. after the assembly of the dishwasher, it is essentially plastic and not stainless steel which is visible to the end consumer on the surface of the washing compartment lower wall. The end consumer sees the use of stainless steel in the washing compartment as a particular quality feature, so that this platform concept thus appears subjectively to the end consumer or user of the dishwasher to be of lower quality.